Soft magnetic mouldable composites (SM2Cs) would be ideal for integrating magnetic core inductors into circuits since they can be fabricated at low temperatures and pressures. However, most of the existing SM2Cs offer either low magnetic permeability (µ´) or low quality factor (Q), especially at high frequencies (> 10 MHz). To address this issue, a bottom-up approach is reported that incorporates designing the composition of the magnetic filler, coating the filler with Polydimethylsiloxane (PDMS) brush, to a state-of-the-art casting process. This procedure has enabled the fabrication of cores with an outstanding combination of µ´ and Q. The µ´ of our cores is 40% higher than the best available data at 10 and 25 MHz which is due to the high packing of cores. Our core also offers one of the highest Q at 10 MHz due to low hysteresis loss and low inter-particle eddy current loss as a result of the polymer brush insulating effect.
